The problem is that multiplication of extended precision numbers in J is slow (quadratic).
----- Original Message ----- From: [email protected] Date: Thursday, April 9, 2009 18:15 Subject: Re: [Jprogramming] Mersenne Prime initialization. To: Programming forum <[email protected]> > > I looked over the essay by roger hui and the: > > pow=: 4 : '*/ *~^:(I.|.#:y) x' > > works ok. > > Regreatably, > > time '<: 2x pow 1257787' NB. takes ~41.0 sec > > I will try:: > > time '<: 2x pow 43112609' > > overnight and see what it takes. > > ----- Original Message Follows ----- > From: Aai <[email protected]> > To: Programming forum <[email protected]> > Subject: Re: [Jprogramming] Mersenne Prime initialization. > Date: Thu, 09 Apr 2009 20:18:24 +0200 > > >Sorry, another try: > > > >http://www.jsoftware.com/jwiki/Essays/Repeated_Squaring > > > > > >-- > >=@@i ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
